1. Field of the Invention
The present invention relates generally to devices for reclaiming natural gas used to power equipment such as a pump in a well head antifreeze system.
2. Related Art
Natural gas and oil wells in geographic areas with colder climates are susceptible to freezing around the well head. Such freezing can damage well pumps, valves, and other equipment, and cause a decrease or loss of natural gas production from the well.
To reduce freezing of the well heads, systems have been developed that pump antifreeze solutions through or around the well head equipment. Often, the pumps that circulate the antifreeze solution are driven by pressurized natural gas from the well. In these cases, a small portion of the pressurized natural gas being extracted from the well is diverted from the pipeline and fed into the antifreeze pump where the pressure from the natural gas drives the pump and circulates the antifreeze. The natural gas is released to the atmosphere after running the pumps.
Unfortunately releasing the natural gas to the atmosphere causes an adverse environmental impact and often counts against allowable emission standards set by government environmental control agencies. Additionally, the amount of gas released to the atmosphere from these pumps amounts to lost revenues from sale of the natural gas to consumers.
Reclaiming the natural gas from the pumps into the pipeline has not been a viable option because of several problems. For example, when the natural gas is used to drive the pump, contaminants can be introduced into the natural gas that make the gas unfit for further consumption. For instance, the pumps used to circulate the antifreeze can develop leaks in the seals separating the antifreeze lines from the natural gas lines. When this occurs, antifreeze can enter the natural gas line and mix with the natural gas. The antifreeze makes the natural gas unfit for use.
Furthermore, occasionally an antifreeze pump will suffer a catastrophic failure such that antifreeze is dispersed from the pump in large quantities. Antifreeze is a toxic substance that can have an adverse environmental impact and any such failure requires containment and clean up which is expensive. Additionally, the natural gas well may need to be shut down during the clean up which adds lost production revenue to the total costs of clean up and repair of an antifreeze pump failure.